<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="utf-8" />
    <title>Just a test</title>
</head>

<body>``
    <a href="javascript:popUp('http://www.example.com/');">Example1</a>
    <a href="#" onclick="popUp('http:\/\/www.example.com/'); return false;">Example2</a>
    <!-- 平稳退化 -->
    <a href="http://www.example.com/" onclick="popUp(this.getAttribute('href'));return false;">Example3</a>
    <a href="http://www.example.com/" onclick="popUp(this.href);return false;">Example4</a>

    <!-- 分离JS -->2                        
    <a href="http://www.example.com/" class="popup">Example5</a>


    <script src="example.js"></script>
    <script src="scripts/popUp.js"></script>
</body>

</html>